Method and apparatus for regulating clocks



AMmh 31, v1936. A, FPOLE 2,035,759

METHOD AND APPARATUS FOR RECrULA'lING4 CLOCKS Filed May 4', 193;

' Patented Mar. 31, 1936 i IWTHD AND APPARATUS FR REGULATING CLOCKS Application May d, 193i, Serial No.' 534,758

i8 Claims.

My invention is an improved method and appai-attrs for regulating clocks.

One of the objects of my invention is the provision of means for transforming the beats of the clock escapement into an alternating or periodic current of a frequency which is an integral'multiple of saidbeats and of a higher frequency. Another object of my invention is the provision of a current of standard frequency with which said 10 clock controlled current may be compared, and a further object of my invention is the provision of means of making such comparison conveniently and accurately. A further object of my invention is the provision of means whereby a regulation of any desired degree of precision may be made by first making ai regulationA to acertain degree of precision and then increasing the frequency ofthe comparison currents to make a. regulation of a much higher degree of precision. These and other objects of my invention will be described in the following specification and pointed out in the claims.

In order to carry out my invention, I provide means for transforming the beats of the clock to be regulated into an alternating current of the same frequency as the beats of the clock. I then take this A. C. current and send it through an amplifier and then through a series of multivibratorsto raise this clock frequency to a relatively 3@ high one. I then provide a source of standard frequency, and means for causing said standard frequency to interfere with the clock governed frequency. By noting the interference beats I can bring the clock under test quickly and pre- L- cisely into correct regulation.

My invention will be best understood by refer# ence to the accompanying figures of which Fig. 1 a diagram of the circuits necessary to carry my herein described method of regulation, rigs. 2, 3, and 4 are various modifications of the apparatus necessary to detect when the clock is in correct regulation. Referring to Fig. 1, I0 represents the framework of a clock in which is mounted a balance II rotating on a shaft I2 and if whose oscillations are governed by a. hair spring tomary roller pin il which is actuated by the fork i3 rotatably mounted inthe framework on a staff i3, and having rigid therewith the impulse pins 2i) and 2i which are actuated by an escapement wheel rotatably mounted on a shaft 23. The escapement wheel is driven by the pinion 24 into .which engages a fourth wheel 25 rotatably mounted on the shaft 26. The parts thus far described will be recognized as parts common to any clock and are shown simply for the sake of illustration. 0` I shall now proceed to describe the parts necessary to carry out my herein described invention.

The clock Ill is put on a shelf 2I which is preferably made of thin wood,. and near said shelf is a telephone transmitterl 28 in a circuit including a battery 29 and the primary 30V of an induction coil. Obviously the ticks of the clock escapement will affect the transmitter and be transformed' into an undulating current whose frequency is the same as theticks of the clock. I shall assume that the clock makes four beats per second, this being the usual frequency for alarm clocks, and, therefore, as a result of the ticking of the clock, the circuit containing the transmitter 28 has an undulating current of a frequency of four cycles per second. The induction' coil is4 provided with a secondary winding 3| which leads to amplifier 32 to bring the current up to the level necessary to actuate a multivibrator 33 which multiplies the frequency 15 times. tors are well known in the radio art, I shall not describe them. an example of such a multivibrator is found in 'my prior Patent 1,928,793.

Their function is to take' a current ofv one frequency and to transform this current into a fre- 35 quency of a higher'integral multiple of the frequency which is supplied to them. The multivibrator may include a filter, if necessary, so as to suppress all frequencies except the desired one.

As a result of the stepping up of the frequency o by themultivibrator 33, the output of ,this multivibrator is a current of 60 cycles per second, which current is kept in step with the rate of the clock. The multivibrator 33 is led to asecond multivibrator 34 which hasa factor of 12, thereby raising 45 the Gil-cycle current'to a frequency of 720, more or less, depending upon the rate of the clock un- -der regulation. The current from the multivibrator 34 is led by means of a double pole switch 35 by conductors 4U and 4I to an amplifier 42 50 which is provided with an adjustable transformer. having windings 43 and 44, to raise the current to the proper level to illuminate a test lamp 45. As

a result 'of the apparatus just described, we have a. frequency of 720 cycles per second going through Since these multivibra- '30' the lamp 45, this frequency being an exact multiple of the number of vibrations of the clock under test. i

It remains now to describe the method of securing a current of constant frequency with which to'compare the current governed by the clock under test. To this end I have provided a standard pendulum or time measuring element 54 which, for the sake of the present illustration, may be taken as vibrating two times per second. The bob of this pendulum is provided with a projection 65 which cooperates with the light wire 66 in a circuit containing a battery 63. a conductor 63a, and the primary 62 of an induction coil. Thus at every swing of the pendulum, the circuit 65-65 will be closed and consequently a currentl i of two cycles per second will be sent through the `ing`62 and leads to an amplifier 80, which is similar to the amplifier 42,*which raises the standard currentof two cycles pei: second to the proper level to actuate a multivibrator 59 which multiplies the frequency of this current ve`times. As before, this multivibrator may be provided with a filter so as .to allow only current of 10 cycles per second to get through. The multivibrator 581s' connected to a multivibrator 58 which raises the vfrequency eight times. Consequently its output is a frequency of 80 cycles-per second, which is led to a multivibrator 51 having a multiplying factor of nine, which raises the standard current to a frequency of 720 per second. A double pole switch 52 connects the multivibrator 51, by means of conductors 58 and 5I,

to an amplifier 49 which raises the current to the proper level to affect an adjustable transformer having windings 48 and 41, the'latter being connected in series with the lamp 45 and a galvanometer 46.-

It will be apparent that if the rate of the clock under test is exactly four beats per second, the lamp 45 will remain either permanently bright o r permanently darkpbut if the frequency controlled by the clock ders from the standard frequency, then theY lamp' 45 will make one iiash for each cycle gained or lost by the clock-controlled frequency induced in the winding 44. The

scheme is exactly similar to the method of comparing the frequency of two electric generators by means of a synchronizing lamp. Noting the flash of the lamp 45, the operator then manipulates the regulator i4 so as to accelerate or re tard the rate of the clock. It is easy to tell in which direction to move the regulator since if it is moved in the wrong direction, the lamp 45 will flash oftener. The regulator is moved until the lamp 45 reaches a steady state, either of 'light or darkness, and the clock under test is then removed from the shelf 21 and another clock put in its place.

At this point it is to be noted that the particular frequency of '720 per second chosen to illustrate my invention' was taken for the reason that there are 1440 minutes in a day, and consequently, if

gain or lose two minutes per day. If the operator regulates the clock so thatthe lamp 4 5 makes one flash in two seconds, then the rate of the clock inder test departs from the true rate onel minute per day.

In the event that it is desired regulate the switch 35 by the conductors 88 and 69, and it will" .bev seen that if the switch 35 is moved to the left, then the frequency deliveed to the winding 44 will be afrequency of 7200 cycles per second.

In order to step up the standard current to this frequency, I have provided a multivibrator" 10, having a multiplying factor of 10, which is connected by conductors 1| and 12 to the points 55 and 56 of the double throw switch 52. Throwing this switch to the right will step up the standard current to a frequency of `7200. This, of course, will simply increase the precision of measurement by 10. One flash of lamp 45 per second, when the high frequency current is on, will correspond to a gain or loss of one-tenth of 120, or 12 seconds per day. Obviously, the stepping up of thecurrent can be carried to any desired degree of precision.

A galvanometer 48 responsive to alternating current may be provided as an indicator in the event that the iiashing of the lamp 45 is not easily visible. Swings of the galvanometer needle will indicate fiashings of the lamp 45 and give like information as to the relative frequencies of the standard current and tha der test.

For the sake of clearness I have shown the switches 35 and 52 as separate, in practice they would be combined into one so that when 35 was thrown 52 would be thrown also. l

In Fig, 2 I have shown a modication of my device in which instead of using a current from a master clock as the standard current, I have used the ordinary regulatedA. C. current used for driving synchronous motor clocks. In work such as regulating alarm clocks, akregulated current of this kind is accurate enough, and itis unnecessary to have the Vstandard frequency equipment of the pendulum 64 and its associated multivibrators. In this arrangement the coil 43 in said figure is connected to the multivibrator 33 so as to get a current of a frequency o f'60 cycles per second to compare withthe 60 cycle current from the mains 13 and 14. InFig. 3 I have shown another modification of the detecting apparatus, in that a telephone receiver 19 is placed in the circuit 44-41. 'I'his receiver will, of course,l give a sound corresponding to the frequency of the alternating current sent through it,`and this sound will have beats if the two frequencies are not exactly alike. Key 1l', manipulated by a button 18, and key 44, manipulated by a button 8|, are provided so that either the test circuit or the standard may be cut off to tell readily whether theclock under test is running fast or slow.

In Fig. 4 I have shown the lamp 45, which, in

this case, should be a neon lamp, illuminating a rotating disc 82 divided into sectors mounted-on a shaft 83 of a synchronous motor 84 which is run from the lstandard current by means of an adjustable transformer whose windings are 85 and 88. 'I'his stroboscopic method of determining the rate of the clock under test will be ap- -parent to those skilled in the art without further description. 4

While I have described my improvement as applied to the timing of a clock, it is obvious that c rents, and making itis equally applicable to the regulating of watches, since it is only necessary to make the transmitter circuit 28 and the amplier 32 sufllciently sensitive to pick up the ticks of afwatch put o n the shelf 2T. By this means one is able to bring a-watch to the rate of a few seconds per day in three or four minutes. Many variations may be made from the precise apparatus herein described without departing 'from the spirit of my invention, since I claim:

1. The method of regulating clocks which comprises transforming the periodic sound of a clock into a pulsating current, stepping up said pulsating current to a high frequency current, and

comparing said high frequency current with a standard frequency current.

2. The method of regulating clocks which comprises transforming the periodic sound of a clock into a pulsating current, stepping up said pulsating current to a high frequency current, and comparing said high frequency current, by interference with a standard frequency current. 'c

3. The method of regulating clocks which comprises transforming the periodic sound of a clock into a pulsating current, stepping up said pulsating current to a higher frequency current, comparing the interference beats of said higher frequency current with a standard frequency current, correcting the rate of said clock accordingly, then stepping up both the clockgoverned high frequency current and the standard frequency current to still higher frequency curinterference beats.

4. In an apparatus for timing clocks the combination of means responsive to the periodic sounds of said clock, said means acting to control an alternating current in step with said sounds; means of transforming said current into a periodic current of high frequency; a source of` current of standard high frequency; means to cause said periodic current to interfere with said standard frequency current and an indicator to respond to the frequency of said interference.

5. In an apparatus for timing clocks the com-l rent of a frequency higher than that of saidI sounds, a source of current of standard frequency,

means to step up said last mentioned current to a higher frequency and means of comparing the frequencies of said high frequency currents.

'7. In mechanism for regulating a timepiece having an escapement, the combination of means for creating a periodic current whose periodicity -is synchronized with and hears a multiple rela# a, second comparisonof theby causing said currents to interfere and cause beats, and a lamp to detect said beats.4 9. The method of comparing the operation of a commercial clock with ay standard'reference clock, which comprises impressing upon a circuit an undulating current having afrequency synchronized with the time measuring element of the commercial clock, impressing onv the same circuit a periodic current having a frequency synchronized with the time measuring element of the reference clock, continuously comparing the frequencies of said currents, and regulating the rate of the time measuring element of the commercial clock until the frequency of the undulating current bears an unchanging and'desired synchronized relation to the`frequency of the periodic current.

10. vThe method of regulating a timepiece which comprises producing a time regulated, periodic, visual signal at an integral multiple of the frequency desired'for the time measuring part of said time piece, and producing another periodic, visual signal at an integral multiple of the actual frequency of the time measuring part of said timepiece, and regulating the operation of ksaid time measuring part until the frequency of current in time with said sounds, means for increasing the frequency of said periodic currents in an exact multiple relation, a source of standard. frequency currents, and a common circuit into which both said currents are introduced and indicating means in said circuit. whereby said two frequencies may be compared.

13. In an apparatus for timing a commercial clock, means responsive to the periodic sounds of the clock under test for producing a periodic current in ltime with said sounds, means for increasing the frequency of said periodic current in an exact multiple relation, a source of 'standard frequency currents, and stroboscopic means for comparing said high frequency and said standard currents. Q

14. In an apparatus for testing a commercial clock, means responsive to the periodic sounds of the clock under test for producing a periodic current in time' with said sounds, means for increasing the frequency of said current in an exact multiplerelationship, a source of standard frequency currents, a motor driven by said source of currents. a visual indicator driven by said motor, light producing means actuated by said current of increased frequency, whereby said two currents may be compared as to frequency by the action of said light falling on said indicator.

15. In an apparatus for testing a commercial clock, means responsive to the periodic sounds 75 of the clock under test 'for producing a periodic current in time with said sounds, means for increasing the frequency of said currents in an exact multiple relationship, a source of standard. frequency currents, a common circuit into which said standard currents and said' currents of raised frequency are introduced, and audible signal means in said circuit whereby said two frequencies may be compared.

16. In an apparatus for testing clocks, the combination of a source of standard currents, a motor driven thereby, indicating means driven bysaid motor, means responsive to the periodic sounds of the clock under test for producing a periodic current intime with :said sounds, light producing means actuated in timed relationship with said periodic currents, whereby the instantaneous position of said indicating means Acan be determined by allowing said light to fall on said indicator, and thev relativefrequency of the clock undertest with respect to the standard currents be de ed thereby.

17. In `an apparatus for testing clocks. the

-combination of a source of standard currents, a 25 motor driven thereby, indicating means drivenl Vby said motor, lmeans responsive to the periodic sounds of the clock under test for producing acombination of a source oi standard currents, a

motor driven thereby, an indicator driven by said motor, means responsive to the periodic sounds ofthe clock under test for producing a periodic current in time with said sounds, an oscillating circuit under the control of said periodic currents for tering the character of said periodic current, l t producing means actuated by said altered current, and positioned so that the light produced thereby illuminates said indicator,

whereby the relative frequency of said clock and said standard currents may be determined. 

